Optic disc photography remains the mainstay for recording the state of the optic nerve head (ONH) for glaucoma patients. Longitudinal changes in the ONH condition are monitored by meticulous study of the structures, such as the cup to disc ratio and vessel orientation variations. Although the ophthalmologists are quite adept at this task, they can only make qualitative judgments. That is, because of time constraints and the lack of quality computerized tools, they normally cannot make precise measurements in order to detect small changes that occur early in the disease. An ONH Image Analyzer is proposed that will apply an "Active Shape Model" (ASM) as a means for segmenting features and produce a statistical representation of the "shapes" in the OHN for the patient's longitudinal images. The ASM is a relatively new technique used for modeling structures that may have similarities, but can vary in the details. The ASM, as used in this application, will capture the longitudinal variability in the same person's ONH. The ASM will produce statistical representation of the changes in spatial location and shape of vessels. It will also be applied to other structures, such as the optic disc and cup, to detect and quantify subtle changes in their shape and size. The use of ASM for analyzing the changes in the ONH structure has not been described in the literature. Because of the pervasiveness of this classical photographic technology, the successful application of ASM for analyzing ONH changes will make a significant impact on its clinical use for many more decades. Specific aims are: 1) to demonstrate that subtle changes in vessels location on the OHN can be detected and measured precisely, and 2) to correlate changes in the vessels in the ONH due to the progression of glaucoma. [unreadable] Commercialization Potential: The ONH Analyzer System can provide quantitative information for the changes in structure and configuration of the optic disc and retinal vessels and thus has the potential to advance the diagnostic techniques and time to diagnosis for glaucoma. The system minimizes user involvement and uses existing digital photographic technology currently used in the offices and clinics of ophthalmologists. As such, the commercial impact of this device is significant from a cost and time to market assessment as well as integration to existing equipment perspective. [unreadable] [unreadable]